All You Ever Wanted to Know About Fire Extinguishers . . .

This is the new style of labeling that shows thisextinguisher may be used on Ordinary Combustibles,Flammable Liquids, or Electrical Equipment fires.This is the new labeling style with a diagonal red linedrawn through the picture to indicate what type offire this extinguisher is NOT suitable for. In thisexample, the fire extinguisher could be used onOrdinary Combustibles and Flammable Liquids fires,but not for Electrical Equipment fires.Types of Fire ExtinguishersDry Chemical extinguishers are usually rated for multiple purpose use. Theycontain an extinguishing agent and use a compressed, non-flammable gas as apropellant.Halon extinguishers contain a gas that interrupts the chemical reaction that takesplace when fuels burn. These types of extinguishers are often used to protectvaluable electrical equipment since them leave no residue to clean up. Halonextinguishers have a limited range, usually 4 to 6 feet. The initial application ofHalon should be made at the base of the fire, even after the flames have beenextinguished.Water These extinguishers contain water and compressed gas and should onlybe used on Class A (ordinary combustibles) fires.Carbon Dioxide (CO2) extinguishers are most effective on Class B and C(liquids and electrical) fires. Since the gas disperses quickly, these extinguishersare only effective from 3 to 8 feet. The carbon dioxide is stored as a compressedliquid in the extinguisher; as it expands, it cools the surrounding air. The coolingwill often cause ice to form around the “horn” where the gas is expelled from theextinguisher. Since the fire could re-ignite, continue to apply the agent even afterthe fire appears to be out.